If you want contests to be viewed more "fair" I would suggest having a batch of websites showcased each week, with the highest 2 or so from each round moving on and ultimately making it to the facebook style poll.
Problem is with 200 entries, at 20 showcases a week, that is 10 weeks, then another week for the final winner... just takes too long.
I agree it would be too hard to navigate through each website, judge its' layout, features, graphics etc, and do this for 50 websites in a week (which would make the contest about a month long instead of 3 months).
I do like the contests as there aren't too many examples in the Customer Gallery and I tend to get locked in a certain layout style for a bit. Viewing websites made with the exact extensions I have, gives me many ideas for creative websites.
Maybe you could include a section in our accounts for uploading websites created. There could be a section for uploading a few images, short description, the url and what extensions were used. Then on the main website an area can be designated to pull a random finished site from a random users account. Anyone who sees it will get a preview of the site, what extensions were used, the short description but could click on it to go to the actual site. Then maybe it also opens up the users profile and goes to that finished website page and other users see a rate and comments section. Click on number of stars from 1 to 5, and provide a sentence or two of what could be improved or what was liked.
Top rated sites each year get pooled into a big contest. This way it is purely user rated votes, as long as there is enough traffic that will actually want to rate websites here and there. Just spitting out some ideas!